DRAFT: This module has unpublished changes.
DRAFT: This module has unpublished changes.

DRAFT: This module has unpublished changes.

Equipment

  • Data collection system
  • pH sensor
  • Magnetic stirrer
  • Ring Stand
  • 2 100 mL Beakers
  • 2 10 mL Beakers
  • 100 mL Volumetric Flask
  • Erlenmeyer flask
  • Right angle clamp
  • Funnel
  • 0.6 g KHP
  • 0.40 g NaOH
  • 10 mL of pH 4 buffer
  • 10 mL of pH 10 buffer
  • Wash bottle with deionized water
  • Titrater Machine

Procedure

  1.  Weigh out 4.2 grams of NaOH. Dissolve in quickly in about 50 mL of water in 250 mL Erlenmeyer flask. Mass of NaOH used: 4.2013 g
  2.  Minimize the exposure of NaOH to air because the carbon dioxide content of air can react with NaOH.
  3.  Carefully transfer the solution into a 1 L volumetric flask and fill the flask to the 1000 mL mark with deionized water.
  4.  Seal the flask with its stopper, invert the flask, and shake gently. Then vent the flask. Mix the solution well.
  5.  Transfer the solution into a 1 L plastic bottle and close it. Make sure the bottle is labeled properly.
  6. Start a new experiment on the data collection system.
  7. Connect a pH sensor and the Rotary Motion sensor to the data collection system.
  8.  Create a dataset for the first derivative of the pH vs. volume in data studio.
  9.  Display the pH on the y-axis of a graph and volume on the x-axis.
  10.   Set up the titrator pump, rinse the syringe on the pump, and set up the titrator accessory.
  11.   Calibrate the pH sensor.
  12.    Add the micro stir bar to the end of the pH sensor.
  13.   Set up the titrant container and replace the cap on the bottle.
  14.    Load the syringe and prime the titrator.
  15.   Measure out about 0.200 grams of KHP to the nearest milligram and record the value in table 1. Wash the KHP sample from the weighing dish with about 50 mL of water into a 180 mL titration jar.
  16.   Repeat step 15 twice to make two more solutions of KHP.
  17.   Add enough deionized water to the solution so that the tip of the pH sensor is covered with solution.
  18.    Turn on the magnetic stirrer at a steady rate.
  19.   Start recording on the data studio. Then press start on the titrator to start titration.
  20.    Continue the titration until it is past the equivalence point and the pH curve flattens.
  21.    Stop recording the data.
  22.    Repeat steps 19-21 for the other two KHP samples.
  23.   Clean the syringe in the titrator.
DRAFT: This module has unpublished changes.
Show Comments (0) and Tags